Furthermore, the researchers observed that the IH associated with OSA is characterized by an altered interaction between the gut and liver, manifested by increased intestinal permeability, endotoxemia, and an overexpression of the endotoxin receptor TLR-4 in hepatocytes, Kupffer cells, and hepatic stellate cells (HSCs). The gene discussed is TLR4; the disease is serum lipopolysaccharide activity.